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COVID-19 Status & Maps
Daily status of the COVID-19 pandemic and its relationship to the trails.
Printed Maps & App
Stay found. Stay informead. Our premium printed topographic maps and matching app for a once in a lifetime adventure
OnLine Data Books
Free online data books for your favorite trail, distances, elevation, climate, way points, terrain & fauna
GPS aware Google maps, your location, topo, hybrid, satellite, trail track, way points, road, weather/snow overlays
Active Fires & Smoke
Know before you go! Get the lastest active fire & smoke information for your favorite trail
Get the lastest snow conditions for your favorite trail. Quantity, coverage, SNODAS, MODIS, historical and multi-year comparisons
Create an extensive hike plan easily configurable to your hiking style. Distances, days, resupply, access points, etc
Create your own fully customizable gear list with weight, pricing and divisable by section.
Exhaustive resource for species ranges along your favorite trail. Includes amphibians, birds, mammals and reptiles.
Complete Gear Lists
Hundreds of complete gear lists by those that walked the walk.
The big picture. Single elevation profile of your favorite trail.
Search for a journal, create a journal, add/edit an entry, configure your journal, EMail updates, integrated Google trail map, PLB locations and more
Print out your favorite trail to 6 feet high. Elevation chart and resupply locations.
Source for trail and site information or just talk about your favorite trail
The John Muir Trail snow report is designed to aid hikers in determining the best time to head into the mountains based on snow conditions. Each hikers skill-set and comfort level with these conditions will differ.
The John Muir Trail snow report uses SNODAS modeled snow data and MODIS reflectivity data. SNODAS gives us a good idea about the quantity of frozen water sitting on the ground, denoted by SWE (Snow Water Equivalence) in inches. Coverage is often poorly represented by SNODAS where snow cover is thin. The 8 day MODIS data, without regard for quantity, shows us what areas were snow covered at some point over the last 8 days. Cloud cover and darkness adversely affects MODIS detection significantly, hence we use the 8 day as opposed to the single day coverage. This is the only combined MODIS/SNODAS JMT snow map on the internet. It's also the only Sentinel-2 data with trail alignments.
Snow page updates November 1st - July 28th
Trail snow is not snow pack. The Postholer snow page focuses on snow on or near the trail, at trail elevation, not on snow condtions thousands of feet lower/higher and miles away from the trail. Ski resort snow reports and snow pack charts are a very poor representation of trail snow conditions.
|Snow Season Probabilities|
|Below Normal||Normal||Above Normal|
|This is not a prediction. This is not an absolute statement of future conditions. It is deterministic based on current and past conditions. This gives insight to April 1st conditions, the closer to April the greater the accuracy.|
SNODAS SWE, Entire Trail
SNODAS/MODIS, Tuolumne Mdw to Crabtree Mdw
Sentinel-2 20m (~65 feet) Snow Cover
SNODAS SWE, Sierra
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